Telescopes, Resolution and Angular Size

Watch the entire series here: Telescopes: the Tools of Astronomy: Astronomy class at William Paterson University: https://youtu.be/hhbardsuB0Q

This is part of my complete intro Astronomy class that I taught at Willam Paterson University and CUNY Hunter. If you want to watch all the videos in the correct order, please visit my website at http://www.jasonkendall.com

A key aspect of telescopes is their angular resolution. Here we discuss what makes up the concept of angular resolution and seeing.

Supplement the videos with "OpenStax Astronomy"
https://openstax.org/books/astronomy/pages/6-thinking-ahead
6: Astronomical Instruments

https://en.wikipedia.org/wiki/Angular_resolution
Angular resolution

http://hyperphysics.phy-astr.gsu.edu/hbase/phyopt/Raylei.html
The Rayleigh Criterion

https://en.wikipedia.org/wiki/Diffraction-limited_system
Diffraction-limited system

https://en.wikipedia.org/wiki/Airy_disk
Airy Disk

https://en.wikipedia.org/wiki/Trigonometric_functions
Tangent of an angle

https://en.wikipedia.org/wiki/Radian
Radian

This is part of Module 5 of 14 which details an entire online introductory college course. This video series was used at William Paterson University and CUNY Hunter in online classes as well as to supplement course material. In the first lecture, Refraction and Reflection, I discuss the obvious point that all telescopes rely on some ability to focus light to a point. The two ways are refraction and reflection. I'll describe what they are in the context of telescopes. Next, I go over angular resolution and seeing. A key aspect of telescopes is their angular resolution. I talk about what makes up the concept of angular resolution and seeing. From her, I go on to focal ratio, magnification, plate scale and related ideas. After that, I chat about the nature of how images are created digitally. We look at it from a hardware point of view, and we see that the current way of doing images relies on tiny boxes. Now that we know how they work, we'll take a look at big telescopes around the world and in space. This is meant as a basic introduction to some of the greatest resources ever constructed. I'm showing off their websites and what the instruments look like. After that, we'll learn about radio telescopes, what they do, what their function is, and some of the major radio facilities around the world. We also examine angular resolution and the need for interferometry in radio telescopes. We'll also lament the loss of Arecibo. From there, we go on to some of the more prominent space-based observatories, what they see, and how they do what they do. We'll learn about JWST, and far behind it is. Last, what can they see when they work well? All Sky Astronomical Surveys. I'll talk about the nature of full-sky surveys. It is highly instructive to make maps of the entire sky, just like it's important to make maps of our spherical Earth. We look at many wavelength bands and how the sky looks at all those wavelengths.